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Satellite-based (2000–2015) drought hazard assessment with indices, mapping, and monitoring of Potohar plateau, Punjab, Pakistan

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Drought is one of the deadly natural disasters that leave tearstained faces and broken dreams in its wake. Lifecycle as we know it comes to a halt during a dry season in a region. The purpose of this study was to observe the temporal and spatial variation of droughts in the rain-fed area of Potohar plateau (22,254 km²), Punjab, Pakistan, from 2000 to 2015, through remotely sensed satellite data, available at the database of Google Earth Engine. Potohar consists of four major districts of the country; Chakwal, Attock, Rawalpindi, and Jhelum. From 2000 to 2015, indices calculated were: standard precipitation index (SPI), standard precipitation evapotranspiration index (SPEI), vegetation condition index (VCI), precipitation condition index (PCI), soil moisture condition index (SMCI), and temperature condition index (TCI). In this study, SPI and SPEI pointed out meteorological droughts in 2000, 2001, 2002, 2004, 2009, 2010, and 2012, which were taken as base years for drought in the study. The study concluded that the main factor involved in the drought severity is not one, but rather a combined accumulation of temperature, precipitation, and soil moisture. Soil moisture and precipitation affect the vegetation in the area more so than the temperature of the land surface. Soil moisture was heavily influenced by the amount of precipitation. The land surface temperature was seasonal dependent. The surface temperature was warmest in Chakwal and Attock, while Rawalpindi had the coldest land surface temperature. Soil moisture increased with precipitation. Soil moisture was high in Rawalpindi and Attock during drought years.
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Environmental Earth Sciences (2020) 79:23
https://doi.org/10.1007/s12665-019-8751-9
ORIGINAL ARTICLE
Satellite‑based (2000–2015) drought hazard assessment withindices,
mapping, andmonitoring ofPotohar plateau, Punjab, Pakistan
RamlaKhan1· HammadGilani1 · NaveedIqbal2· ImranShahid1
Received: 27 March 2019 / Accepted: 27 November 2019 / Published online: 16 December 2019
© Springer-Verlag GmbH Germany, part of Springer Nature 2019
Abstract
Drought is one of the deadly natural disasters that leave tearstained faces and broken dreams in its wake. Lifecycle as we
know it comes to a halt during a dry season in a region. The purpose of this study was to observe the temporal and spatial
variation of droughts in the rain-fed area of Potohar plateau (22,254km2), Punjab, Pakistan, from 2000 to 2015, through
remotely sensed satellite data, available at the database of Google Earth Engine. Potohar consists of fourmajor districts of
the country; Chakwal, Attock, Rawalpindi, and Jhelum. From 2000 to 2015, indices calculated were: standard precipitation
index (SPI), standard precipitation evapotranspiration index (SPEI), vegetation condition index (VCI), precipitation condi-
tion index (PCI), soil moisture condition index (SMCI), and temperature condition index (TCI). In this study,SPI and SPEI
pointed out meteorological droughts in 2000, 2001, 2002, 2004, 2009, 2010, and 2012, which were taken as base years for
drought in the study. The study concluded that the main factor involved in the drought severity is not one, but rather a com-
bined accumulation of temperature, precipitation, and soil moisture. Soil moisture and precipitation affect the vegetation in
the area more so than the temperature of the land surface. Soil moisture was heavily influenced by the amount of precipita-
tion. The land surface temperature was seasonal dependent. The surface temperature was warmest in Chakwal and Attock,
while Rawalpindi had the coldest land surface temperature. Soil moisture increased with precipitation. Soil moisture was
high in Rawalpindi and Attock during drought years.
Keywords Drought monitoring· Satellite-based drought indices· Google Earth Engine· Spatial–temporal variation·
Potohar plateau· Pakistan
Introduction
Drought is one of those disasters that do not have one spe-
cific reason for its occurrence. Sometimes, less rainfall than
usual can cause a short-term drought (Palmer 1965), and
then comes the time when a long-term drought is caused by
a number of factors like air temperature, land surface tem-
perature, soil moisture, and other precipitation phenomena.
When a region is going through a drought situation, it faces a
severe shortage of water, and since water is the basic need of
all living things, its deficiency affects lives catastrophically.
Lifecycle as we know it comes to a halt during a dry season
in a region (Memon 2012). A drought has different meanings
for people from different occupations. Drought is the sort
of phenomena that influences all irrespective of which field
of life they belong to. Numerous studies have proven that
hazards like floods and drought hit the unprivileged sector
of the society more severely than others (Kurosaki 2015).
Experts have divided drought into different classes
throughout history, but in the modern world, drought has
four major types; meteorological, agriculture, hydrologi-
cal, and socioeconomic (Wilhite and Glantz 1985). All four
types of drought usually do not occur at the same time, but
rather, the prolong duration of one leads to the occurrence
of the other (Zargar etal. 2011). Sometimes, few of them
might occur simultaneously, but that is rarely the case.
Droughts are usually determined in terms of their drastic
impacts, but there is still a need for a physical method that
could calculate drought (Vicente-Serrano etal. 2012). In
other words, there are a number of probabilistic methods,
but the need for a deterministic method is still necessary.
* Hammad Gilani
hammad.gilani@gmail.com
1 Institute ofSpace Technology, Islamabad, Pakistan
2 Pakistan Council ofResearch inWater Resources, Islamabad,
Pakistan
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... This region is believed to originate in the Cambrian era along with the Himalayan mountainous range, which extends through India to Tibet and Nepal (Hughes et al., 2019). Precipitation is relatively high in Rawalpindi and Jhelum districts, while the other districts receive relatively irregular and low rainfall (Rashid and Rasul, 2011;Khan et al., 2020). Temperature range is more or less similar up to moderate elevations, but higher elevations are cooler, often receiving snowfall from December to February. ...
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